I was especially interested in listening to the account of the author's trip from Skagway/Dyea up over the White Pass and then down the other side to Lake Bennett, the Yukon River and on to Dawson, as I had lived in that richly historical area myself for some years in the 1990s.
I find it curious that some unique aspects of the 1898-99 period are not mentioned at all by Ms Sullivan. For instance, such is the case with the historical figure who, even unto the present day, is still remembered in Skagway, Alaska: the brutish gangster Soapy Smith, see http://en.wikipedia.org/wiki/Soapy_Smith.
Also, an anomaly: the White Pass & Yukon Railway only went into service in summer of 1900, so if the author traveled there in 1899, she could not have been on that train in the manner she describes. At the date of her trip, they were still blasting away stone in White Pass to make place for the railway bed.
On the Yukon side of the Pass, at Lake Bennett, everyone had to stop and build rafts or boats to continue on down the Yukon. This arduous, frustrating aspect was an essential phase of the journey to the gold fields, but it goes unmentioned here. http://en.wikipedia.org/wiki/Bennett_Lake
The bandit Soapy Smith enforced a monopoly on transport of all goods carried from Dyea across the White Pass through to the Yukon: all packers carrying loads for prospective miners had to pay him a cut. It is curious that this author's friend, whom she reports as having crossed there with a party of some 40 people sometime in 1898, did not report that hustle to her. http://en.wikipedia.org/wiki/Chilkoot_Pass
It is perhaps little-known, but every miner had to bring wth him six months' worth of provisions through that crossing, several tons' worth, otherwise he wouldn't have been allowed by Customs to continue. Consequently the loads transported over the Pass by individuals were humungous and required the services of packers, without which the crossing could take a solitary miner months to accomplish. One didn't just walk over Chilkoot Pass with a simple backpack and carry on; the do-it-yourself ferrying of provisions required multiple trips back and forth. The packers were usually local Indians who, in the end, probably salted away more money than most of the miners.
Firearms were not allowed into the Yukon and they were confiscated by the Northwest Mounted Police posted at Chilkoot Pass. This policy was an attempt to pre-empt violence and crime in Dawson and in the gold fields. Maybe it worked? One would think this would have been a noteworthy fact to report.
Dawson City had a very famous gambling saloon in those days, Diamond Tooth Gerty's, going full-blast 24/7. It still exists. No mention of this is to be found in her account. Another notable feature was that a section of Dawson was a red-light district that housed only girls dedicated to providing services to the miners - the ones who had some paydirt and the enthusiasm to indulge. Not your usual kind of town; yet that goes unmentioned, also.
Canadian author Pierre Berton (1920-2004) was born in Dawson and wrote a book on the Gold Rush there, titled "Klondike, The Last Great Gold Rush 1896-1899". I guess that would be a good source of authoritative info.
Overall this is a very good yarn and it's spun in an interesting way. The reader does a superlative job. But one needs to take the story as it is. Yes, it is an absorbing adventure and it contains a lot of anecdotal material. But it interweaves fantasy with fact and makes some surprising omissions on the part of an observer who ostensibly was there. Insofar as reliable historical facts are concerned, this book is not the place to seek same.

An interesting travel book and the reader, Karen Cummings does an excellent reading.